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For understanding the mercury(Hg)pollution level and corresponding ecological risk in agricultural watershed of Three Gorges Reservoir areas,thus a typical watershed,Wangjiagou,located in Fuling,where is in interior zones of Three Gorges Reservoir areas,was selected as study objective.Meanwhile ArcGIS geo-statistics module was conducted for investigation the Hg contents and distribution characteristics in soils of different types of landuses including dry land,farmland,woodland and settlements.Also corresponding Hg pollution level and ecological risk were assessed.The results suggested that soil Hg contents in this watershed ranged from 9.47 to 94.57 ?g kg-1,and mean value was 34.23±16.23 ?g kg-1.Higher Hg contents in surfaces of soils were observed in woodland,followed by farmland and settlement.The Lowest was found in dry land.Surfaces of soils significantly showed Hg accumulation,and obviously inverse correlation between soil Hg contents and soil depths was also observed in this study.Additionally,geo-statistics analysis showed a weak spatial correlation of soil Hg contents in this watershed,indicating spatial distribution of soil Hg in this watershed mainly were influenced by several natural factors such as atmospheric wet-dry deposit,vegetation coverage and topography,instead of by anthropogenic interference.Overall confirmative soil Hg pollution was not found in this watershed,which showed very lower pollution index(-0.081),but a moderate potential ecological risk still existed(ecological risk index was 57),of which woodland was the relative highest potential risk.The total capacity of Hg in this watershed is 25.39 kg,which dry land accounts for 69%.